Understanding the geographical distribution of plague and other vector diseases is helpful for the disease prevention and control. It is important to analyze the factors affecting the geographic distribution of the vector diseases,and then to predict their occurrence trends. In this study,the relationship between the species richness of host rodents and environment factors nationwide,and the principal factors that affected the rodent plague,were analyzed on the basis of environment data and the geographical distribution of rodent epizootic and host rodents. The results show that the highest species richness of host rodents was in the boundaries of arid and monsoon regions,with the highest positively correlated to altitude difference. The species richness of host rodents was relatively higher in regions where rodent plague had occurred,and relatively lower in non-plague regions. Factor analysis on the environmental variables which affected the occurrence of rodent plague reveals that numbers of vector fleas, annual temperature, rainfall, average relative humidity and sunny hours are factors and the climate factor played a dominant role;that landscape factor,which was composed of altitude differences and numbers of vegetation, soil and geomorphic types was another principal factor;and that the third factor was topography and host. Regions where rodent plague may occur might spread together with the migration of the host rodents under conditions of national climate change to more aridity and warmth.